Conjugated diene/monovinylarene block copolymers with multiple tapered blocks
US5393838A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 1993 |
| Grant date | Feb 28, 1995 |
| Priority date | — |
| Expiry date | Dec 6, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F297/044
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for preparing polymodal tapered block copolymers in a polymerization process by sequentially charging: (a) an initiator and monovinylaromatic monomers in the presence of a randomizer; (b) an initiator and monovinylaromatic monomers; (c) a mixture of monovinylaromatic and conjugated diene monomers; (d) a mixture of monovinylaromatic and conjugated diene monomers; (e) an initiator and monovinylaromatic monomers; (f) a mixture of monovinylaromatic and conjugated diene monomers; (g) a mixture of monovinylaromatic and conjugated diene monomers; (h) conjugated diene monomers; and (i) a coupling agent. The copolymers and blends thereof are particularly useful for packaging applications which require good environmental stress crack resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.